There are several more sorting algorithms I could have gone into, but I had to stop somewhere. I'd like to learn about bitonic sort, signature sort, etc. So I added another few videos to the sorting section that I'll get around to.

What I really like about sorting is the terse code needed to do something very powerful. Even though comparison-based sorting theoretically can't do better that O(n log n), that's pretty darn good. Given the right constraints, such as all your keys to sort are the same length and a small k (for digits, 0..9), you can switch to radix sort and rock O(n) sorting.